Pregnancy Trimesters: Each Stage of Pregnancy

When you are expecting or thinking about conceiving, you may wonder what happens through each of the pregnancy trimesters. As the stages of pregnancy progress, so do the changes within the mom and baby.

While no two pregnancies are the same, there are things that usually happen through the weeks.

There are three trimesters in pregnancy. Pregnancy is an average of 40 weeks, so the pregnancy trimester weeks are each between 13 and 14 weeks.

• First trimester: Weeks 1–13
• Second trimester: Weeks 14–26
• Third trimester: Weeks 27–40

Your estimated due date is calculated based on your last period so to find it, add 40 weeks to the date of your last period. From there, you can calculate when you will be in each of the stages of pregnancy.

For more info on each of the trimesters and the specific changes of mom and baby, read the full article.